Julie and Ben spent five weeks in the US and have just returned to their home in Killingworth, North Tyneside. Julie said: “It’s simply a miracle. “Ben can stand comfortably by himself for about 20 to 30 seconds, he is spending all day on his walker and sticks, while part of his physio takes place on a treadmill. It is unbelievable what has happened to him.”

Ben said: “It’s good to walk, I can walk with sticks now and I’m doing well on my treadmill.”

Julie added: “Dr Park at the St Louis Children’s Hospital was sent from God, he is a miracle worker and no words can describe how we feel.

“Ben is a different boy from when he went to America. He stands, walks with his walker or sticks and can sit on the floor with his legs out in front of him without falling over.

“He was so stiff before, but now he can wriggle his toes. He’s never been able to do that before and now his ankles aren’t tight. We could see an instant difference.”

The operation involves complex procedures including electrically stimulating muscles to the spine.

Julie, 37, said: “Ben also had to have his hamstrings lengthened to finish off his treatment in America. We know we have a long road ahead of us as he has daily physio, which can be tough.

“Before, when Ben tried to walk, at most he could only manage half an hour on his walker. Because of the stiffness he would go on his tiptoes and would cross his legs in front of one another, but now that doesn’t happen and he’s doing it like anyone else.”

Ben is now splitting his day walking with his frame and sticks instead of being in his wheelchair when he goes to Westmoor Primary School.

Julie, who also has nine-year-old daughter Jessica, added: “He’s loving it and his classmates think it’s fantastic. We set out to get this operation because it is not available on the NHS. We hope everything goes to plan.”